Existing wireless communication systems include a User Equipment (UE), a Radio Access Network (RAN), and a Core Network (CN). The UE may be connected to the CN through a dedicated channel. The dedicated channel may be used for operations including circuit-switched voice transfer, packet-switched voice transfer or data transfer. In the Wideband Code Division Multiple Access (WCDMA) network, CELL-DCH state refers to the state in which the UE is engaged in the dedicated channel. In the Global System for Mobile Communications (GSM) network, the Traffic Channel (TCH) state refers to the state in which the UE is on a dedicated channel. The GSM network uses the TCH channel for the transfer of voice, circuit-switched data and circuit-switched related signaling.
While it is engaged in a dedicated channel, however, a UE may get stuck on the dedicated channel. This may happen due to an error or a fault in at least one UE, RAN and CN. When the UE is stuck on the dedicated channel, the UE and the RAN keep performing actions that are necessary to maintain the channel. For the WCDMA Radio Access Technology (RAT), the actions include UEs sending MEASUREMENT REPORT messages and RANs sending MEASUREMENT CONTROL messages and ACTIVE SET UPDATE messages on the relevant Radio Bearers (RBs). In spite of the UE and the RAN performing the necessary actions, no useful data is exchanged between the UE and the CN for a significant period of time. In other words, there is no higher layer signaling and no data transfer over non-signaling RBs carrying user data or voice.
When stuck on the dedicated channel, the UE can suffer from several problems. First, battery consumption is high in a UE stuck on the dedicated channel. The dedicated channel is the highest battery consumption mode for the UE. In the dedicated channel, the UE continually monitors the downlink and transmits on the uplink. Second, this situation also results in the wastage of network resources. Maintaining a dedicated channel for the UE requires a significant amount of RAN resources and bandwidth. When the UE is stuck on the dedicated channel, these RAN resources and bandwidth are wasted, without any useful data being exchanged.
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